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A printing and peeling arrangement comprises an impression drum for supporting a print medium during application of a printing image thereto, and one or more rotating vacuum fingers for applying vacuum via suction caps to the print medium to peel the print medium from the impression drum after print

A printing and peeling arrangement comprises an impression drum for supporting a print medium during application of a printing image thereto, and one or more rotating vacuum fingers for applying vacuum via suction caps to the print medium to peel the print medium from the impression drum after printing. The vacuum finger is mounted for radial motion towards the impression drum and thereby avoids impact damage onto the print medium from the edges of the suction caps that results from a purely rotational approach to the drum.

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1. A printing and peeling arrangement comprising: an impression drum for supporting a print medium for receipt of a printing image,a rotating shaft, andat least one rotating vacuum finger extending from said shaft along a radial axis of said shaft for applying vacuum to said print medium to remove s

1. A printing and peeling arrangement comprising: an impression drum for supporting a print medium for receipt of a printing image,a rotating shaft, andat least one rotating vacuum finger extending from said shaft along a radial axis of said shaft for applying vacuum to said print medium to remove said print medium from said impression drum after receipt of said printing image,wherein a radial component of motion along said radial axis towards said impression drum is applied to said vacuum finger. 2. The printing arrangement of claim 1, wherein said at least one vacuum finger is mounted on said rotating shaft via a cam, and wherein said cam applies said radial component of motion to said at least one vacuum finger. 3. The printing arrangement of claim 2, wherein said cam is configured via a lobe orientated towards said drum. 4. The printing arrangement of claim 3, wherein said at least one vacuum finger has a radius of rotation which is insufficient to reach said drum when not riding on said lobe but which is sufficient to reach said drum when riding on said lobe. 5. The printing arrangement of claim 2, wherein an idling motion of said at least one vacuum finger is provided in which said radial component of motion is not applied to said at least one vacuum finger. 6. The printing arrangement of claim 2, wherein said at least one vacuum finger comprises a suction head for applying said vacuum to said print medium, said suction head having an outer radius greater than an outer radius of said at least one vacuum finger, and said radial component of motion is sufficient to prevent an impact of said outer radius of said suction head with said print medium. 7. The printing arrangement of claim 6, wherein a rate of rotation of said at least one vacuum finger is such as to equalize a velocity of said suction head with said print medium at a point of touch. 8. The printing arrangement of claim 7, wherein said impression drum has a rotation in a first sense when printing and said at least one vacuum finger has a rotation in an opposite sense, thereby to achieve said equalized velocity. 9. The printing arrangement of claim 1, wherein said at least one vacuum finger is connected via a flexible vacuum tube to a vacuum source. 10. The printing arrangement of claim 1, wherein the printing arrangement is part of a multi-color printing arrangement which applies impressions in a spread involving different colors at successive separations. 11. Peeling apparatus for peeling a print medium from an impression drum after application of an impression to said print medium, the apparatus comprising a vacuum finger and mounting therefor, the mounting comprising a shaft and a cam, the vacuum finger being mounted radially about said shaft along a radial axis of said shaft thereby to rotate about said shaft and further being mounted on said cam, said cam being configured with a lobe to transfer a radial motion component along said radial axis to said vacuum finger upon said rotation, the lobe being aligned such that said radial motion component provides a linear approach to said impression drum. 12. Apparatus according to claim 11, wherein an idling motion of said vacuum finger is provided in which said radial motion component is not transferred to said vacuum finger. 13. Apparatus according to claim 11, wherein said vacuum finger comprises a suction head for applying a vacuum to said print medium, said suction head having an outer radius greater than an outer radius of said vacuum finger, and said radial motion component is sufficient to prevent an impact of said outer radius of said suction head with said print medium. 14. Apparatus according to claim 13, wherein a rate of rotation of said vacuum finger is such as to equalize a velocity of said suction head with said print medium at a point of touch. 15. Apparatus according to claim 14, wherein said impression drum has a rotation in a first sense when printing and said vacuum finger has a rotation in an opposite sense, thereby to achieve said equalized velocity. 16. Apparatus according to claim 11, wherein is connected via a flexible vacuum tube to a vacuum source. 17. Apparatus according to claim 11, wherein said apparatus is part of a multi-color printing system which applies impressions in different colors at successive rotations of said impression drum. 18. A method for peeling a print medium from a rotating drum, the drum rotating in a first sense, the method comprising: mounting at least one vacuum finger in proximity to said drum along a radial axis of a shaft,applying vacuum via said at least one vacuum finger to said print medium,rotating said at least one vacuum finger with a rotary motion in a second opposite sense, andapplying a linear component to said rotary motion such as to cause said at least one vacuum finger to extend linearly outwards along said radial axis of said shaft upon approaching said drum to contact said print medium and retract linearly along said radial axis of said shaft upon receding from said drum. 19. The method of claim 18, further comprising providing an idling motion in which said linear component is not applied to said rotary motion of said at least one vacuum finger and said print medium is not contacted. 20. The method of claim 18, comprising: providing an idling motion of said at least one vacuum finger in which said print medium is not contacted,carrying out a predetermined number of rotations of said drum,providing said linear component for a final rotation of said drum, andpeeling said print medium from said drum at said final rotation. 21. The method of claim 20, comprising applying an impression using a different color ink for each rotation of said drum. 22. A method for peeling a print medium from a rotating drum, the drum rotating in a first sense, the method comprising: mounting at least one vacuum finger having a suction cap in proximity to said rotating drum along a radial axis of a shaft,applying vacuum via said at least one vacuum finger to said suction cap,rotating said at least one vacuum finger with a rotary motion in a second opposite sense, andapplying a linear component to said rotary motion such as to cause said at least one vacuum finger to extend linearly outwards along said radial axis of said shaft upon approaching said drum to contact said print medium and retract linearly along said radial axis of said shaft upon receding from said drum.